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1.
Sci Data ; 11(1): 321, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548727

RESUMO

Flexible bronchoscopy has revolutionized respiratory disease diagnosis. It offers direct visualization and detection of airway abnormalities, including lung cancer lesions. Accurate identification of airway lesions during flexible bronchoscopy plays an important role in the lung cancer diagnosis. The application of artificial intelligence (AI) aims to support physicians in recognizing anatomical landmarks and lung cancer lesions within bronchoscopic imagery. This work described the development of BM-BronchoLC, a rich bronchoscopy dataset encompassing 106 lung cancer and 102 non-lung cancer patients. The dataset incorporates detailed localization and categorical annotations for both anatomical landmarks and lesions, meticulously conducted by senior doctors at Bach Mai Hospital, Vietnam. To assess the dataset's quality, we evaluate two prevalent AI backbone models, namely UNet++ and ESFPNet, on the image segmentation and classification tasks with single-task and multi-task learning paradigms. We present BM-BronchoLC as a reference dataset in developing AI models to assist diagnostic accuracy for anatomical landmarks and lung cancer lesions in bronchoscopy data.


Assuntos
Broncoscopia , Neoplasias Pulmonares , Humanos , Inteligência Artificial , Neoplasias Pulmonares/diagnóstico por imagem , Tórax/diagnóstico por imagem , Pontos de Referência Anatômicos/diagnóstico por imagem
2.
J Nat Prod ; 86(10): 2270-2282, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37792632

RESUMO

Persea americana Mill. (Lauraceae), commonly known as avocado, is a well-known food because of its nutrition and health benefits. The seeds of avocado are major byproducts, and thus their phytochemicals and bioactivities have been of interest for study. The chemical components of avocado seeds were investigated by using UPLC-qTOF-MS/MS-based molecular networking, resulting in the isolation of seven new oxindole alkaloids (1-7) and two new benzoxazinone alkaloids (8 and 9). The chemical structures of the isolated compounds were identified by the analysis of NMR data in combination with computational approaches, including NMR and ECD calculations. Bioactivities of the isolated compounds toward silent information regulation 2 homologue-1 (SIRT1) in HEK293 cells were assessed. The results showed that compound 1 had the most potent effect on SIRT1 activation with an elevated NAD+/NADH ratio with potential for further investigation as an anti-aging agent.


Assuntos
Alcaloides , Persea , Humanos , Persea/química , Oxindóis/farmacologia , Benzoxazinas/análise , Espectrometria de Massas em Tandem , Sirtuína 1 , Células HEK293 , Sementes/química , Alcaloides/farmacologia , Alcaloides/análise , Extratos Vegetais/química
3.
Phytochemistry ; 215: 113836, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37619899

RESUMO

Autophagy is a crucial process for maintaining cellular homeostasis by degrading and recycling unnecessary or damaged cellular components. In the process of exploring autophagy regulators in plants, unique nine oligomeric flavonoids linked by the bonding of C-3 and C-4, consisting of three pairs of biflavonoids, linderanidins A-C [(+)-1/(-)-1, (+)-2/(-)-2, and (+)-3/(-)-3], and three trimeric A-type proanthocyanidins, linderanidins D-F (4-6), were isolated from the roots of Lindera erythrocarpa. The structures and absolute configurations of these compounds were determined using various techniques, such as 1D and 2D NMR, mass spectrometry, X-ray crystallography, and electronic circular dichroism. All isolates were evaluated for their ability to regulate autophagy, and compounds (±)-1-(±)-3, (-)-1-(-)-3, (+)-1-(+)-3 and 4 were found to inhibit autophagy by blocking the fusion process between autophagosome and lysosome in HEK293 cells. This study suggests that unique oligomeric flavonoids possessing a C-3-C-4 linkage derived from the roots of L. erythrocarpa are potent autophagy inhibitors.


Assuntos
Flavonoides , Lindera , Humanos , Flavonoides/química , Lindera/química , Células HEK293 , Extratos Vegetais/química , Autofagia , Raízes de Plantas/química
4.
Phytochemistry ; 206: 113521, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36435211

RESUMO

Natural guanidines, molecules that contain the guanidine moiety, are structurally unique and often exhibit potent biological activities. A phytochemical investigation of the leaves of Alchornea rugosa (Lour.) Müll.Arg. by MS/MS-based molecular networking revealed eight undescribed guanidine-flavanol conjugates named rugonines A-H. The chemical structures of the isolated compounds were comprehensively elucidated by NMR spectroscopy, HRESIMS, and circular dichroism (CD) analysis. All isolated compounds were tested for autophagosome formation in HEK293 cells stably expressing GFP-LC3. The results revealed that compounds rugonines D-G showed potential autophagy inhibitory activity.


Assuntos
Catequina , Euphorbiaceae , Humanos , Extratos Vegetais/química , Guanidina/farmacologia , Guanidina/análise , Catequina/farmacologia , Euphorbiaceae/química , Células HEK293 , Espectrometria de Massas em Tandem , Guanidinas/farmacologia , Guanidinas/análise , Folhas de Planta/química , Autofagia
5.
Biomolecules ; 10(5)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375402

RESUMO

Pinus densiflora was screened in an ongoing project to discover anti-influenza candidates from natural products. An extensive phytochemical investigation provided 26 compounds, including two new megastigmane glycosides (1 and 2), 21 diterpenoids (3-23), and three flavonoids (24-26). The chemical structures were elucidated by a series of chemical reactions, including modified Mosher's analysis and various spectroscopic measurements such as LC/MS and 1D- and 2D-NMR. The anti-influenza A activities of all isolates were screened by cytopathic effect (CPE) inhibition assays and neuraminidase (NA) inhibition assays. Ten candidates were selected, and detailed mechanistic studies were performed by various assays, such as Western blot, immunofluorescence, real-time PCR and flow cytometry. Compound 5 exerted its antiviral activity not by direct neutralizing virion surface proteins, such as HA, but by inhibiting the expression of viral mRNA. In contrast, compound 24 showed NA inhibitory activity in a noncompetitive manner with little effect on viral mRNA expression. Interestingly, both compounds 5 and 24 were shown to inhibit nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in a dose-dependent manner. Taken together, these results provide not only the chemical profiling of P. densiflora but also anti-influenza A candidates.


Assuntos
Antivirais/química , Inibidores Enzimáticos/química , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Pinus/química , Extratos Vegetais/química , Animais , Antivirais/farmacologia , Sítios de Ligação , Cães , Inibidores Enzimáticos/farmacologia , Flavonoides/análise , Células Madin Darby de Rim Canino , Camundongos , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Neuraminidase/metabolismo , Extratos Vegetais/farmacologia , Ligação Proteica , Células RAW 264.7 , Terpenos/análise , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/química , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
6.
J Nat Prod ; 82(12): 3249-3266, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31763839

RESUMO

The major class of bioactive metabolites in Gymnema sylvestre, a popular Ayurvedic medicinal plant for the treatment of diabetes mellitus, is oleanane triterpenoids. In this study, a targeted, biosynthesis-inspired approach using UHPLC-qTOF/MS was implemented to elucidate the whole chemical profile of this plant for the standardization of the Vietnamese G. sylvestre variety. The known compounds were first determined to identify the building blocks of the biosynthetic intermediates and the construction rules for synthesizing oleanane triterpenoids in the plant. These blocks were recombined to build a virtual library of all reasonable compounds consistent with the deduced construction rules. Various techniques, including relative mass defect filtering, multiple key ion analysis, mass fragmentation analysis, and comparison with standard references, were applied to determine the presence of these predicted compounds. Conventional isolation and structure elucidation of six of the new compounds were carried out to identify the new building blocks and validate the assignments. Consequently, 119 peaks were quickly assigned to oleanane triterpenoids, and among them, 77 peaks were predicted to be new compounds based on their molecular formulas and mass fragmentation patterns. All the identified metabolites were then classified into different layers to analyze their logical relationships, and a multilayered chemical profile of the oleanane triterpenoids was constructed. This new approach is expected to be practical for characterizing structures of modular secondary metabolites, such as triterpenoid saponins, and for proposing biosynthetic relationships among compounds of the same class of metabolites in medicinal plants.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Gymnema sylvestre/metabolismo , Ácido Oleanólico/análogos & derivados , Análise Espectral/métodos , Triterpenos/metabolismo , Glicosídeos/metabolismo , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/metabolismo , Triterpenos/química
7.
Nat Prod Commun ; 9(5): 659-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25026714

RESUMO

Two new fungal pigments named schweinitzins A and B (1-2), together with (S)-torosachrysone-8-O-methyl ether (3) and emodin-6,8-di-O-methyl ether (4) have been isolated from the methanolic extract of the fruit bodies of Xylaria schweinitzii (Xylariaceae) collected in Cuc Phuong national park, Ninh Binh province, Vietnam, by silica gel column chromatography and preparative HPLC. Their structures were elucidated by spectroscopic analysis such as IR, UV-Vis, 2D NMR and FT-ICR-MS. In addition, two compounds (1 and 3) showed strong cytotoxicity against all four cancer cell lines, KB (a human epidermal carcinoma), MCF7 (human breast carcinoma), SK-LU-I (human lung carcinoma) and HepG2 (hepatocellular carcinoma).


Assuntos
Antracenos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Naftalenos/isolamento & purificação , Xylariales/química , Antracenos/química , Antracenos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Naftalenos/química , Naftalenos/farmacologia , Vietnã
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